How to Sign Up for Contra Costa County's Emergency Alerts - and Why the System Has Multiple Layers
How do I sign up for emergency alerts in Contra Costa County?
Contra Costa County's opt-in emergency notification system is called CoCo Alert and is administered through the county Sheriff's Office. Residents can register online through the county's official website at cccounty.us or cocosheriff.org. During sign-up, you provide your address and contact information - phone, cell, or email - and select your notification preferences. Registration is free.
Is my cell phone automatically enrolled in Contra Costa County emergency alerts?
Your cell phone will automatically receive federal Wireless Emergency Alerts - the loud tone-based alerts used for imminent threats and Amber Alerts - without any sign-up. However, Contra Costa County's local CoCo Alert system, which covers more specific local incidents like neighborhood evacuations, requires a separate opt-in registration at the county's official website. Cell phones are not automatically enrolled in CoCo Alert.
What is the difference between CoCo Alert and Nixle in Contra Costa County?
CoCo Alert is Contra Costa County's primary emergency notification system for urgent life-safety alerts like evacuation orders and shelter-in-place notices, requiring residents to register with their address and contact details. Nixle is a broader public safety platform used by county and city law enforcement agencies for lower-priority advisories, road closures, and community bulletins. Both are free; both are worth signing up for.
Do I need to re-register for CoCo Alert if I move within Contra Costa County?
Yes. CoCo Alert notifications are tied to the specific address you registered, not your phone number or account alone. If you move to a new address within Contra Costa County, you should log back into your CoCo Alert profile and update your location so alerts for your new neighborhood reach you correctly. The county recommends reviewing your profile annually even if you haven't moved.
Are PG&E power shutoff alerts the same as Contra Costa County emergency alerts?
No. PG&E's public safety power shutoff notifications are a completely separate system from CoCo Alert and require independent enrollment directly through PG&E. Signing up for CoCo Alert through the county does not enroll you in PG&E outage or shutoff alerts. Residents who want both types of notifications need to register with each system separately at pge.com and through the county's alert portal.
Wildfires, flooding, hazardous materials incidents and severe weather don't follow county lines, but emergency warnings do - and in Contra Costa County, the system for getting those warnings to residents is more layered than most people realize. Knowing which alerts you're automatically enrolled in, and which ones require you to actively sign up, can make a real difference when something moves fast.
Related: How to Sign Up for Orange County's Emergency Alert System Before the Next Disaster Hits · How to Sign Up for Mariposa County's Emergency Alerts - and Why It Matters More Here Than Almost Anywhere in California
How to Sign Up for Mariposa County's Emergency Alerts - and Why It Matters More Here Than Almost Anywhere in California
How to Sign Up for Inyo County's Emergency Alerts - and Why Residents in This Remote County Should
The Two Main Systems Residents Need to Know About
Contra Costa County operates its public emergency notification system through a platform called CoCo Alert, which is administered through the county's Office of the Sheriff and coordinated with the county's Office of Emergency Services. CoCo Alert is the county's opt-in system for phone and text alerts - it's separate from the federal Wireless Emergency Alerts that push to your cellphone automatically, and it covers a much wider range of local incidents than the federal system does.
Wireless Emergency Alerts (WEA) - those loud, jarring tones your phone makes during an Amber Alert or imminent threat warning - are issued by federal and state authorities and don't require any sign-up. You receive them as long as your phone is on and in range of a cell tower in the affected area. CoCo Alert, by contrast, lets the county reach you at a specific address with hyper-local information: an evacuation order for your neighborhood, a shelter-in-place notice for a chemical release on a nearby highway, or a "be ready" advisory before a storm. Those two systems work alongside each other; they're not interchangeable.
How to Register for CoCo Alert
Registration is handled online through the county's official portal. Residents can search for "CoCo Alert" through the Contra Costa County Sheriff's Office website or the county's Office of Emergency Services page at cocosheriff.org or cccounty.us. During sign-up, you enter the address where you want to receive location-based alerts - your home, a workplace, a family member's address - along with your contact information. You can add a landline, a cell phone, or an email address, and you can register more than one location.
Landline telephones at a registered address in unincorporated Contra Costa County are typically included automatically in the county's emergency call-down system, but the county's guidance has consistently recommended that residents with cellphones sign up explicitly rather than assume they're covered. If you've moved recently, or if your phone number has changed, your old registration may no longer match your current address, so it's worth logging back in to confirm your profile is current.
The sign-up process itself takes only a few minutes. You'll create an account, verify your contact information, and select the types of alerts you want to receive. The system allows you to adjust notification preferences - some residents opt in for all categories, including lower-priority community advisories; others limit notifications to immediate life-safety alerts only.
Nixle and the County's Other Notification Channels
Contra Costa County also uses Nixle, a separate platform used by many California law enforcement agencies, to distribute public safety bulletins and community advisories. Nixle messages tend to be less urgent than a CoCo Alert activation - think road closures, non-emergency law enforcement activity, or neighborhood advisories - but the county and individual city police departments within the county use it regularly. You can sign up at nixle.com using your zip code, or by texting your zip code to 888-777.
Individual cities within Contra Costa County - Concord, Richmond, Walnut Creek, Antioch, and others - may also maintain their own supplemental notification systems or social media channels. If you live within city limits rather than unincorporated county land, it's worth checking with your city's website to see what local channels exist in addition to the county-level system.
See also: How to Sign Up for Inyo County's Emergency Alerts - and Why Residents in This Remote County Should · How to Sign Up for Orange County's Emergency Alert System (And Why It's Not Optional Anymore)
What Happens During an Actual Emergency
When the county activates CoCo Alert for a specific area, the system sends notifications in the order of contact methods you've registered, reaching out by voice call, text, and email. For the most serious emergencies - evacuations, imminent threats - the system can also interface with the statewide emergency broadcast infrastructure. The county's Office of Emergency Services also posts real-time updates during major incidents on the county's official social media accounts and website, which serves as a supplement to direct alerts when cell networks are congested.
CalFire and the East Contra Costa Fire Protection District handle fire response in different parts of the county, and their public information channels can be useful during wildfire events specifically. PG&E's public safety power shutoff notification system is entirely separate from CoCo Alert and requires its own enrollment through PG&E directly - if you're concerned about losing power during high-wind events, that's a parallel sign-up worth completing at pge.com.
A Note on Keeping Your Registration Current
Emergency notification systems are only as useful as the contact information in them. The county's guidance, consistent with best practices from California's Office of Emergency Services, is to review and update your alert profile annually - or whenever you change your phone number, move, or add a household member you want covered. There's no fee to register for CoCo Alert. If you're a renter and have moved between addresses in the county, your previous registration won't follow you automatically.
This is general information, not legal or public-safety authority - always verify current sign-up steps, alert system details, and contact information directly with the Contra Costa County Office of Emergency Services and the Contra Costa County Sheriff's Office at cccounty.us and cocosheriff.org, as platforms and processes can change.